Anomaly-driven inverse cascade and inhomogeneities in a magnetized chiral plasma in the early Universe

Understand

By making use of a simple model that captures the key features of the anomalous Maxwell equations, we study the role of inhomogeneities on the evolution of magnetic fields in a chiral plasma.

• We find that inhomogeneities of the chiral asymmetry by themselves do not prevent the anomaly-driven inverse cascade and, as in the homogeneous case, the magnetic helicity is transferred from shorter to longer wavelength helical modes of the magnetic field.
• However, we also find that the evolution appears to be sensitive to the effects of diffusion.
• In the case when diffusion is negligible, the inverse cascade slows down considerably compared to the homogeneous scenario.